Alchemy — the Mixtures
Half farming, half physick, half fire — three halves, which is the point. The same salts feed a field, ease a body, or throw a spark.
The three overlaps
🌱 Farming
Saltpetre (potassium nitrate) as a nitrate fertilizer; wood ash (potash) to sweeten soil; lime; compost teas.
⚕️ Physick
The old materia medica — where a soil amendment, a remedy, and an oxidizer are the same compound seen three ways.
🎆 Fire
Saltpetre + charcoal + sulphur is black powder; the colorant salts (strontium=red, copper=blue, barium=green) are the same salts a chemist and a gardener know.
The point of the list is the overlap: potassium nitrate is fertilizer, historic remedy, and the heart of black powder. Each entry gets its history, its chemistry, and its safety as the section grows.